Blog commenting, availability cascades, and the autism-vaccine debate

In his blog, the Sports Illustrated writer and all-around genius/great guy Joe Posnanski frequently refers to his commenters as “brilliant readers.” His point is that they often prompt him to look at issues from a different perspective, which improves his ability to create a thought-provoking blog, which prompts more reader comments–you get the idea.

My hope is that the same type of community can be established here. That will undoubtedly be a challenge. Having written a book about baseball, I know sports are a topic about which people can get very emotional…but it’s nothing compared to child-rearing/health-care/vaccine safety/autism. I’ve thought a lot about the best way to oversee/moderate comments — more on that later — but for now, I’m incredibly happy to see that there is already some real dialogue going on.

To wit: the back-and-forth on yesterday’s post about Jay Gordon and breastfeeding. First: props to him for responding to my post, and doing so in a way that was meant to engage and not provoke. (Sullivan makes the same point in his comment.) He and Liz Ditz — and I can assure you that these two will not be going out to dinner together anytime soon — have both been tweeting about how important it is to listen to/read the opinions of people we disagree with.

This issue–and I know I’ve been saying this a lot, but it’s true–is one that comes up a lot in The Panic Virus. The technical term for what happens when you only listen to those who agree with you it is an availability cascade, which, I write: (all of the below quotes are from the book)

describes how the perception that a belief is widely held—the ‘availability’ of that idea—can be enough to make it so. In this instance, the believability of the notion that vaccines cause autism has grown in proportion to the number of people talking about it, as opposed to the theory’s actual legitimacy.

Anyone who has studied the Internet knows this is a frequent phenomena online–and one which has been a huge factor in this debate:

Even when you know that an online community selects for a certain type of person—say, politically minded liberals or ardent conspiracy theorists—sustained encounters with a small group of likeminded people almost inevitably lead to the conclusion that everyone thinks the way you do. In the summer of 1999, the CDC’s and AAP’s joint statements on thimerosal served as a catalyst for parents who up until that point had not considered that vaccines might have played a role in their children’s conditions.

And when those parents banded together, they helped create a movement that influences health policy and vaccination practices to this day.

Today, more than a decade after the thimerosal issue first became public, the people who are convinced that vaccines cause autism and those who believe in the accuracy of the dozens of scientific studies have basically stopped speaking. There’s a lot of shouting, occasional threats, some lawsuits — but very little actual conversation. Instead, you have partisans who become ever-more convinced that their opponents are evil monsters…and that’s not good for anyone.